1. Field of the Invention
The present invention relates to an in-vehicle communication device and a communication control method, etc. that can automatically answer a caller device that sends a call when a telephone device located in a vehicle receives the call.
2. Description of the Prior Art
In recent years, accidents caused by drivers who talk on telephones in their hands during driving have occurred frequently. Therefore, various kinds of hands-free systems that make it possible to talk on the telephones without holding them have been proposed. However, it causes a driver a distraction and increases danger to answer a call and talk when there is the incoming call during driving, for example, while he is driving at a high speed.
Therefore, in order to reduce danger involving an incoming call and talking on the phone during driving, the in-vehicle mobile phone system that stops a ring tone and records a caller""s message after reproducing an automatic voice answer message when there is an incoming call during driving has been developed (the Japanese Laid-Open Patent Application No. H11-4190).
FIG. 1 is a block diagram that shows the conventional in-vehicle mobile phone system that is disclosed in the above Japanese Laid-Open Patent Application.
As shown in FIG. 1, the in-vehicle mobile phone system 900 includes an antenna 910, a mobile phone unit 920, in-vehicle kit 930 (a control block 931, a recording/reproducing unit 932), an ECU (engine control unit) 940, a parking brake unit 950, a microphone 960 and a loudspeaker 970.
The control block 931 decides whether a vehicle is running or not based on speed information which is outputted from the engine control unit (ECU) 940 and information on operational condition of a parking brake which is outputted from the parking brake unit 950. When there is an incoming call on the mobile phone unit 920 in the running vehicle (that is, the speed is more than 0 and the parking brake is not in operation), the control block 931 switches the ring tone of the mobile phone unit 920 to stop or turn down, and counts the number of calls received during driving. It sends a message that xe2x80x9cI am now drivingxe2x80x9d which is recorded in advance in the recording/reproducing unit 932 to the caller, and then records the caller""s message. When the vehicle stops, the control block 931 reproduces the caller""s messages which are recorded in the recording/reproducing unit 932 using the loudspeaker 970 based on the number of the calls.
This system makes it possible to reduce danger involving an incoming call and talking on the phone during driving and deliver the message that xe2x80x9cI am now drivingxe2x80x9d to the caller without answering the call.
However, the conventional hands-free system sends the caller a fixed message, a message that xe2x80x9cI am now drivingxe2x80x9d, for example, every time there comes an incoming call during driving. Therefore, according to the conventional system, the caller can only understand that the receiver (the driver) is in a difficulty in answering the call because he is driving, but cannot obtain more detailed information. As a result, the caller has to call the driver over and over after a certain time of period. Also, the caller may be worried about the driver all the time until he gets a call from the driver because he cannot understand the situation of the driver and the vehicle.
Accordingly, the present invention is available to solve these problems, and it is the object of the present invention to provide an in-vehicle communication device and a communication control method that make it possible to prevent a caller from calling repeatedly or becoming uselessly worried even if a driver cannot answer the call because he is driving.
In order to achieve above-mentioned object, the in-vehicle communication device according to the present invention is an in-vehicle communication device that automatically answers a caller device that sends a call when a telephone device located in a vehicle receives the call including: an in-vehicle sensor that detects a vehicle condition; a communication interface for the telephone device; and a control device that controls the telephone device via the communication interface, wherein the control device acquires a vehicle condition which is detected by the in-vehicle sensor, judges whether a driver""s answering the call is dangerous or not based on the acquired vehicle condition when the control device detects the call to the telephone device, prepares an answer message including vehicle information that depends upon a running condition of the vehicle at the time when the control device judges that the driver""s answering the call is dangerous, and sends the prepared answer message to the caller device.
As a result, when the driver cannot answer the call, not a fixed message but the information that depends upon the running condition of the vehicle at that time is sent back to the caller. Accordingly, the caller can obtain fresher and more information on the conditions of the driver and the vehicle than the fixed message and is relieved from anxiety and uneasiness.
Here, the control device may judge that the driver""s answering the call is dangerous when the vehicle condition detected by the in-vehicle sensor goes beyond a predetermined threshold value. For example, the vehicle condition is judged based on at least one of a speed, an acceleration, a steering wheel angle, an operational condition of a parking brake, vertical, lateral and longitudinal movements of the vehicle, and whether the vehicle is in a dangerous zone or not.
As a result, a dangerous condition is judged using not only the operational condition of the parking brake but also the information indicating the danger level such as the speed and the acceleration, so it can be accurately judged whether the driver""s answering the call is dangerous or not. Accordingly, troubles can be avoided such that an automatic answer works for the incoming call to the driver in a not-dangerous condition, or on the contrary, the driver has to answer the call because the automatic answer does not work even in a dangerous condition.
Also, the threshold value may be variable. As a result, by setting the threshold value himself, the driver can set the automatic answer in accordance with his individuality such as his driving technique and experience.
Also, the in-vehicle communication device further includes a map information storing unit operable to store map information that specifies divided zones indicating whether the driver""s answering the call is dangerous or not, wherein the control device may use, as the vehicle condition, whether a current location of the vehicle is in a dangerous zone specified by the map information or not. As a result, since it is judged to be a dangerous condition and the automatic answer works for the incoming call, for example, when the vehicle is located in a dangerous zone such as an entrance to a tunnel and an intersection, the safety of the driver is secured.
Also, the in-vehicle communication device further includes an in-vehicle information terminal device which is located in a vehicle, wherein the control device may prepare the answer message by reading out vehicle information from the in-vehicle information terminal device. For example, the in-vehicle information terminal device is a car navigation device, and the control device may use, as vehicle information, (A) at least one of (i) a destination, (ii) a route to the destination, (iii) a current location, (iv) a distance to the destination and (v) an estimated arrival time to the destination, which are held by the car navigation device; or (B) a combination of the vehicle condition and at least one of (i) (ii) (iii) (iv) and (v).
As a result, since the caller can not only understand the condition that the driver is driving but also anticipate to some extent how long the condition will continue, he can wait for the driver""s answer without feeling anxiety or uneasiness.
Also, the control device may send the answer message in a form of an e-mail to the caller device. As a result, since the caller can obtain the information on the vehicle""s running condition by the e-mail, reception errors can be avoided such as missing hearing or hearing wrong which may occur in the case of the automatic voice answer. That is, the caller can obtain the driver""s condition without fail.
Here, the control device may acquire an e-mail address of the caller from the telephone device, and send the e-mail to the acquired e-mail address. And the in-vehicle communication device further includes an address book storing unit operable to store in advance an address book in which a telephone number and a corresponding e-mail address are registered, wherein the control device may specify an e-mail address of the caller device by referring to the address book stored in the address book storing unit based on a telephone number of the caller, and send the e-mail to the e-mail address of the caller.
As a result, the e-mail address of the caller can automatically acquired when the driver receives a call, and the automatic answer by an e-mail becomes possible.
The present invention can be realized not only as the above-mentioned in-vehicle communication device, but also as a communication control method for an automatic answer for a hands-free device, or a program including the communication control method as a step. The program can, of course, be distributed via a recording medium such as a CD-ROM or a transmission medium such as the Internet. Note that Bluetooth is a registered trademark of The Bluetooth SIG Inc.